Objective To describe the significance of pericardial effusion (PE), mitral regurgitation (MR) and impaired systolic function in predicting coronary artery lesions (CAL) at diagnosis and follow-up in Kawasaki disease (KD).

Design Echocardiographic records on admission, at 1–3 weeks of illness, and at 6–8 weeks of illness were retrospectively retrieved in children with acute KD treated by intravenous immunoglobulins.

Setting, patients The study included 194 consecutive children (113 male; median age 2.1 years) in a paediatric cardiology tertiary care centre, from 1988 to 2007.

Results Overall, children with CAL (64/194) were more likely to have PE (OR=3.00, CI 1.34 to 6.72) and MR (OR=2.51, CI 1.22 to 5.16) at diagnosis; PE was the sole echocardiographic abnormality associated with CAL in multivariable analysis. These abnormalities were predictive of the presence of CAL at the first echocardiography in the acute phase of the disease only. MR, systolic dysfunction and PE were not associated with persistence of CAL in the convalescent phase. Male gender, CAL size and resistance to immunoglobulin treatment were independent factors predictive of the persistence of CAL.

Conclusions Children with MR or PE should undergo careful assessment of coronary status at diagnosis. However, PE or MR at diagnosis is not predictive of persistent CAL at follow-up.